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arXiv · 0812.1309

Voltage-Controlled Surface Magnetization of Itinerant Ferromagnet Ni_(1-x)Cu_x

Igor V. Ovchinnikov·Kang L. Wang
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Abstract

We argue that surface magnetization of a metallic ferromagnet can be turned on and off isothermally by an applied voltage. For this, the material's electron subsystem must be close enough to the boundary between para- and ferromagnetic regions on the electron density scale. For the 3d series, the boundary is between Ni and Cu, which makes their alloy a primary candidate. Using Ginzburg-Landau functional, which we build from Ni_(1-x)Cu_x empirical properties, ab-initio parameters of Ni and Cu, and orbital-free LSDA, we show that the proposed effect is experimentally observable.

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Igor V. Ovchinnikov, Kang L. Wang. 2008-12-06. Voltage-Controlled Surface Magnetization of Itinerant Ferromagnet Ni_(1-x)Cu_x. https://doi.org/10.1103/physrevb.78.012405

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